Effect of the Inclination Angle on Slippage Loss in Gas-Liquid Two-Phase Flow

Abstract

The lifting efficiency and stability of gas lift well are affected by the socalled slippage-loss effect in gas-liquid two-phase flow. The existing studies on this subject have generally been based on vertical and horizontal wells. Only a few of them have considered inclined pipes. In the present work a new focused study is presented along these lines. More specifically, we use the non-slip pressure drop model with Flanigan’s fluctuation correction coefficient formula (together with the parameters of slippage density, slippage pressure drop and slippage ratio) to analyze the influence of the inclination angle on slippage loss for different conditions (different gas-liquid superficial velocity and pipe diameters). Moreover, the “standard regression coefficient method” is used for multi-factor sensitivity analysis. The experimental results indicate that slippage loss is affected by multiple factors, and the influence of the inclination angle on slippage loss is less significant than other factors. The change of the slippage pressure drop with the superficial velocity of gas-liquid is similar to that of the total pressure drop. The inclination angles of 45° and 60° have the greatest influence on slippage loss. The correlation between slippage density and slippage ratio is not obvious. Using the so-called slippage ratio seems to be a more accurate option to evaluate the degree of slippage loss.